This enables Ignition unconditionally for all code that is destined for
optimization with TurboFan. This ensures all optimization attempts will
go through the BytecodeGraphBuilder and that the AstGraphBuilder pipe is
dried out in practice.

R=mvstanton@chromium.org

Review-Url: https://chromiumcodereview.appspot.com/2427953002
Cr-Commit-Position: refs/heads/master@{#40462}